Rock-drill



JQPERDUE. BOOK DRILL;

(No Model.)

Patented June 6, 1882.

way; (57664. :(4 5w UNITED STATES JAMES PERDUE, OF BELLEFONT, VIRGINIA, ASSIGNOR OF THREE-FIFTHS TO B. D. M. JONES, OF SAME PLACE, AND GEORGE INGION, DISTRICT OF COLUMBIA.

W. DYER, OF WASH- ROCK-DRILL.

SPECIFICATION forming part of Letters Patent No. 259,278, dated June 6, 1882.

Application filed May 16, 1881. (No model.)

To all whom it may concern:

Be it known that I,JAMES PERDUE, of Bellefont, in the county of Nottoway and State of Virginia, have invented a new and useful Improvement in Rock- Drills, of which the following is a specification in such full, clear, and exact terms that any one skilled in the art to which it applies mightmake and use the same, reference being bad to the accompanying drawin gs, forming a part of this specification.

My invention relates to that class of drills used for drilling stone, and particularly to such drills as are operated by hand.

Heretofore such drills have been used either by hand,the drill being held by one man while his companion strikes it with alarge hammer, or by a mechanical device, whereby the drill is raised and let fall, the impact of the blow doing the work. It is this latter class of drills which is improved upon in my invention, and therein lies its object.

In the accompanying drawings, Figure 1 is a perspective view of my improved drill, while Fig. 2 is a View of the spirally-grooved collar hereinafter described.

Similar letters refer to like parts.

A A is the frame supporting the drill-shaft B, having in its lower end the drill 0. Upon the top of the shaft B is a weight, E, whose size is regulated to suit the diameter of the hole being drilled, thus rendering the blow of the drill sufficient todo the work. By means of the screw m this weight E is made adjustable on the drill-shaft, thus affording means by which the length of said shaft can be in creased. Fixed upon the drill-shaft B is the spirallygrooved collar D. (Shown also in Fig. 2.) This collar is also made adjustable on the drill-shaft by means of the screw m. By the construction thus far described it will be clearly seen that the length of the drill-shaft can be made to correspond to the depth of the hole to be drilled without the change of the drill proper.

At right angles with the drill-shaft B is the shaft F, operated by the crank H K. Fixed 5 upon the shaft F is the tappet-wheelGr, having three or more tappets or lifters, which, when the crank is turned to the right, rise into the spiral grooves inthe collarDand turn the drill 0 through about one-sixth of a revolution, when the tappet, having arrived. under the shoulder d at the upper end of the spiral groove, lifts the drill to a sufficient height for a stroke, and, passing from under the shoulder, allows the drill to drop. The shaft F continuing to rotate, the next tappet, taking into the next spiral groove, turns and afterward lifts the drill and lets it fall again, and so on, repeating the operation in regular strokes. The grooved collar D is adjusted to height as the drill O descends in the progress of the drilling by a simple set-screw.

The special point of improvement is the adjustability of the weight and grooved collar, by means of which the length of the drill-shaft can be greatly increased.

Having now described my invention, I claim- In a rock-drill, the combination of the drillshaft B, provided with an adjustable weight, E, and an adjustable spirally-grooved collar,

D, with the shaft F, rotated by means of crank H K, and provided with tappet-wheel Gr, all the parts arranged and operating substantially as described and shown.

This specification signed and witnessed this 26th day of April, 1881.

13, JAMES 1 PER-DUE.

mark.

Witnesses:

ALONZO PERRY, 7 JAMES ALEXANDER PERRY. 

